Even by their own impressive standards as straight-talking controversialists, Donald Trump and Rosie O'Donnell must have surprised themselves by the intensity of the vitriol they flung at each other this week. She called him a bankrupt snake-oil salesman. He called her a fat-assed slob and threatened to sue. It is fair to say there was no love lost.

The spat erupted earlier this week after Mr Trump, the property tycoon best known for sacking people at the point of a finger on The Apprentice television show, which he produces and hosts, made what he saw as an act of generosity.

It related to Tara Conner, this year's Miss USA - an award which Mr Trump controls as the owner of the Miss Universe Organisation. Mr Trump extended his largesse towards Ms Conner after she became embroiled in a succession of news reports on her underaged drinking in New York clubs.

She turned 21 - the legal age to drink - this week, but not before she had been paparazzied in compromising situations. Mr Trump announced on Tuesday that despite the publicity he would allow her to retain the title so long as she went into alcohol rehabilitation.

Enter Ms O'Donnell. On her morning talkshow, the View, on Wednesday, she said the display of Mr Trump's forgiveness had annoyed her "on a multitude of levels".

Lowering her voice in imitation of the tycoon and flipping her hair over her head in the Bobby Charlton-style that is the Trump trademark, she said: "I think this man is sort of like one of those, you know, snake-oil salesmen in Little House on the Prairie."

The former stand-up comic is not known for her moderation and true to form she did not stop there.

Mr Trump was the moral compass for 20-year-olds in America, she said, and yet he was also the man who "left the first wife, had an affair, left the second wife, had an affair. He inherited a lot of money, wait a minute ... and he's been bankrupt so many times where he didn't have to pay."

Nor is Mr Trump known for turning the other cheek and true to form, he lashed back. "Rosie O'Donnell is disgusting, I mean both inside and out," he said on a rival television show, the Insider.

"Take a look at her, she's a slob. She talks like a truck driver."

He denied he ever went bankrupt, and said he would sue "because it would be fun. I'd like to take some money out of her fat-ass pockets."